Nicotine fortification of smoking products

ABSTRACT

Controlled amounts of nicotine may be supplied to a tobacco product or acceptable substitute smoking composition by adding to the base small amounts of a nicotine derivative of galacturonic acid or polymannuronic acid which on pyrolysis of the composition release small amounts of nicotine into the smoke stream.

United States Patent 1191 Perkins et al.

[451 Jan. 21, 1975 NICOTINE FORTIFICATION OF SMOKING PRODUCTS [75]Inventors: Paul Raymond Perkins, Portishead;

Christopher Ralph Bale, Keynsham, near Bristol, both of England [73]Assignee: Imperial Tobacco Group Limited,

London, England [22] Filed: Sept. 12, 1972 [21] Appl. No.: 288,329

[30] Foreign Application Priority Data Sept. 23, 1971 Great Britain44370/71 [52] US. Cl ..131/2,131/17, 131/9, 424/361,131/144 [51] Int.Cl. A24b 03/14, A24b 15/04 [58] Field of Search 131/2, 17; 424/361 [56]References Cited UNITED STATES PATENTS 3,529,602 9/1970 Hind et al.131/2 Primary Examiner-Melvin D. Rein Attorney, Agent, or Firm-Larson,Taylor and Hinds [57] ABSTRACT 7 Claims, No Drawings NICOTINEFORTIFICATION OF SMOKING PRODUCTS This invention concerns a smokingproduct e.g. tobacco, hand rolling tobacco, pipe tobacco, reconstitutedtobacco sheet, substitute smoking materials free from tobacco, or blendsand mixtures thereof and cigarettes, cigars or cigarillos containingsuch materials and concerns the problem of maintaining or increasing thenicotine content of the smoke whilst avoiding an undesirable level ofparticulate matter in the smoke from the product.

Various techniques are known for reducing particulate matter in thesmoke of a smoking product. For example it is well known to filter outparticulate matter but in so doing nicotine is also filtered and thusthe resulting smoke from the smoking product is poorer in nicotine aswell as in particulate matter.

A further example is the use of reconstituted tobacco sheet in blendsfor smoking products. By appropriate choice of component materials andcontrol in the preparation and manufacture of the sheet it is possibleto reduce the yield of particulate matter in the resulting smokingproduct. Unfortunately such sheet, prepared from mixtures of tobaccostem, tobacco lamina and/or general tobacco offals, generally contains alower concentration of nicotine than the other tobacco grades in theblend such that a nicotine deficiency exists.

A third example is the use of synthetic and substitute smoking materialsin which particulate matter is reduced considerably. As with theprevious examples however the overall delivery of nicotine in the smokeis reduced in proportion to the amount of such material incorporatedinto the smoking product since the natural nicotine content of suchsmoking materials is zero.

To avoid the disadvantages of the above examples it is proposed toincrease the nicotine content of a smoking product whereby, although thelevel of particulate matter can be reduced, the level of nicotine can bemaintained or even increased. Efforts to do this in the past have beendisappointing since the percentage of nicotine added to the product andsubsequently appearing in the smoke has been very low. Furthermore thelevel of the added nicotine drops considerably with time and shelf lifeis poor. It is an object of the present invention to overcome suchdisadvantages.

According to the present invention there is provided a smoking materialcontaining a nicotine derivative of a polyuronic acid.

Preferably the acid is a polygalacturonic or polymannuronic and thederivative is nicotine pectinate or nicotine alginate respectively.

Where nicotine pectinate is used this is formed from pectinic acidhaving a degree of esterification of up to 50 percent preferably 30 35percent. Furthermore the acidity is from 1.5 to 3.5 milli equivalentsper gram, preferably from 2.0 to 3.5 milli equivalents per gram(m.eq/g).

lf pectinic or alginic acids available are not of the desired acidity,they can be de-ashed or freed from inorganic materials by washing withacid, preferably with aqueous isopropanol (specific gravity 0.880)contain ing hydrochloric acid in the ratio of 1 part by volume ofhydrochloric acid to parts by volume of aqueous isopropanol (specificgravity 0.880).

The base materail can be tobacco lamina. stem (mid rid), reconstitutedsheet or synthetic smoking material which is tobacco free.

The product preferably contains at least 1 percent and up to 30 percentof the nicotine derivative on a dry weight basis. Preferably the smokingproduct contains 3 to 13 percent of the nicotine derivative on a dryweight basis.

The invention also includes a smoking product containing a material setforth above.

The invention also includes a method of making a smoking material as setforth above.

The invention is illustrated by the following two series of examples.For use in these series the following samples of nicotine alginate andnicotine pectinate were produced:

A first sample (sample 1) of nicotine pectinate was produced from citruspectinic acid obtained from lemon peel and having a degree ofesterification of 35 percent and acidity of 3.1 m.eq/g and l00gms ofthis acid was mixed with 30gms of water until the water was absorbed anda free-running powder was obtained. SOgms of percent pure technicalgrade nicotine was stirred into the powder to produce an homogeneouspaste of crude nicotine pectinate. This was left 24 hours to completethe chemical reaction and the resulting product was ground to a coarsepowder. One litre of ethanol was added to the powder which was filtered,washed with five ml portions of ethanol and two 50mls portions ofdiethyl ether and dried so that unreacted nicotine was removed. Theresulting powder had a nicotine content of 25 percent. This nicotinepectinate will hereinafter be referred to as Sample 1.

A second sample hereinafter referred to as Sample 2" of nicotinepectinate was prepared from citrus pectinic acid prepared from lemonpeel and having a degree of esterification of 35 percent and acidity of2.7m.eq/g. With this pectinic acid, nicotine pectinate was prepared inexactly the same way as that set out above with reference to sample 1but the resulting nicotine pectinate had a nicotine content of 23.8percent.

A powder of nicotine alginate (Sample 3) was prepared using alginic acidof acidity 5.2m.eq/g supplied by British Drug Houses Ltd. of Poole,Dorset under Reference 27898 in their 1970 Catalogue. Nicotine alginatewas prepared from this alginic acid in exactly the same way as samples 1and 2 of nicotine pectinate were prepared and as described above, andthe resulting nicotine alginate had a nicotine content of 31.5 percent.

A fourth sample sample 4 of nicotine pectinate was prepared in solutionform but in this case technical grade nicotine 90.8 percent pure andsupplied by British Drug Houses was used with lemon peel pectinic acidhaving a degree of esterification of 35 percent and acidity of2.7m.eq/g. A solution of 1200 g of pectinic acid in 18.5 litres of waterwas prepared and 333g of nicotine added. The dissolved nicotinepectinate derivative contained 20 percent nicotine and the finalsolution contained 1.5 percent nicotine on a weight for weight basis.

A fifth sample sample 5 of nicotine pectinate was prepared according tothe procedure of sample 4 but in this case a sugar beet pectinic acidwas used having a degree of esterification of 30 percent and an acidityof 1.7m.eq/g. The resulting nicotine pectinate solution had a nicotinecontent of 1.5 percent on a weight for weight basis.

Sample 6 was a nicotine alginate solution made according to the methodof sample 4 above but in this case the acidity of the alginic acid was3.6m.eq/g with a negligable degree of esterification. The nicotinealginate solution had a nicotine content of 1.5 percent on a weight forweight basis.

Sample 7 was a nicotine pectinate solution prepared from the samematerials as sample 4 except that litres of water was used instead of18.5 litres. The resulting nicotine pectinate solution contained 1.8percent nicotine on a weight for weight basis.

The first series of experiments was conducted using 9 examples, of whichexamples l6 involved fortification using nicotine pectinate or nicotinealginate and examples 79 were controls or standards. The second seriesinvolved 11 examples of which numbers 10l7 were fortified with nicotinealginate or nicotine pectinate and examples l820 were controls orstandards.

SERIES 1: EXAMPLES l9.

EXAMPLE 1 A sheet of reconstituted tobacco was prepared in the followingmanner.

A mixture of 255gms of winnowings and 225gms of general offal (both ovendry weight) were soaked in 4.5 litres of tap water for one hour. Theslurry was repeatedly passed through a Premier 84 colloid mill initiallyset to a gap of 0.01 inches between the stones. The gap was decreased by0.003 inches after each pass until the slurry remained in a colloidalstate.

gms of sample 1 nicotine pectinate were added to the tobacco slurry andmixed using a Silverson mixer. The mixture was then passed through thecolloid mill set at gap zero to remove any lumps which may have formeddue to coagulation.

The slurry so formed was cast onto a pre-siliconed stainless steel sheetto a wet sheet thickness of 1.2mm. The sheet was dried in air and thenslightly moistened to facilitate removal from the stainless steel sheet.The tobacco sheet so prepared was tested for nicotine content, cut andplain cigarettes of mm circumference and 70mm length (commonly referredto in U.K. as class B cigarettes) were manufactured on a Hauni Babycigarette making machine and smoked using a standard smoking machineprocedure in which five equal weight cigarettes are smoked on a FiltronaCSM 14 machine to a 20mm butt using a 2 second, 35ml puff every minute.The particulate matter was collected on a Cambridge glass fibre filterand the water-free and nicotine-free particulate matter (P.M.) wasmeasured and the nicotine delivery determined. To do this, the wetdeposit on the Cambridge filter was weighed, the nicotine was determinedby steam distillation followed by spectrophotometric analysis (Willitsmethod) and water determined by gas chromotography. The resultantdeposit is particulate matter (P.M.) which is water and nicotine free.The tests were repeated three months later and the results are tabulatedon the accompanying Table 1.

EXAMPLE 2 A sheet of reconstituted tobacco was prepared in exactly thesame way as that described above with reference to Example 1 andnicotine pectinate of sample 1 was again added but in this example36.3gms of the nicotine pectinate were added to the same tobacco slurry.

The cast sheet was removed from the band, tested for nicotine contentcut and made into plain cigarettes 25mm circumference and 70mm longwhich were subsequently tested by the standard method described inExample 1 for particulate matter and nicotine deliveries in the smoke.The tests were carried out soon after manufacture and three months laterand the results are set out in Table 1.

EXAMPLE 3 A sheet of reconstituted tobacco was again manufactured inaccordance with the details set out in Example 1 above, but in this caseSample 2 of the nicotine pectinate was added to the slurry, 21.4gms ofthe pectinte being used for the same amount of the tobacco slurry.Again, nicotine content of the sheet was measured. the sheet was cut,made into plain cigarettes of 25mm circumference and 70mm length andanalysed by the standard method described in Example 1 for particulatematter and nicotine deliveries in the smoke both immediately aftermanufacture and three months later. The results are set out in Table 1.

EXAMPLE 4 EXAMPLE 5 The sheet of reconstituted tobacco described abovewith reference to Example 1 was again made strictly in accordance withthe specification but 16.2gms of the nicotine alginate (sample 3) wereadded to the tobacco slurry. Again the sheet was but and made into plaincigarettes 25mm circumference and 70mm long. These were tested by thestandard method described in Example l for particulate matter andnicotine deliveries in the smoke and the results are set out in Table 1.

EXAMPLE 6 The sheet of example 5 was made up but 36gms of sample 3nicotine alginate were added and the resulting sheet cut, made intoplain cigarettes 25mm circumference and 70mm long and tested by thestandard method of example 1 for particulate matter and nicotinedelivery in the smoke.

EXAMPLE 7 To provide one control against which one could analyse theresults of storage of the samples set out above, a sample of acommercially available low tar yielding reconstituted tobacco sheet ofnicotine content 0.78 percent was made into plain cigarettes 25mmcircumference and 70mm length and tested by the standard method ofexample 1 for particulate matter and nicotine delivery in the smoke onthe same dates as examples 1 to 6 were tested. This particular controlsheet is recognised as being relatively stable for nicotine content andthus provided a suitable standard against which to measure the nicotineloss from the samples 1 to 6.

EXAMPLE 8 The tobacco sheet described above with reference to examples16 was made but without any additive i.e. no nicotine pectinate ornicotine alginate, simply tobacco winnowings and offal with water Thenon-additive sheet so made was cast on the stainless steel band and.when removed, was cut, made into plain cigarettes 25mm circumference and70mm long and analysed by the standard method of example 1 forparticulate matter and nicotine delivery in the smoke.

EXAMPLE 9 To provide a comparison and standard by which the result setout in Table 1 can be compared, a plain cigarette 25mm circumference and70mm long and available on the U.K. market was obtained and analysed inthe same way as the other examples for particulate mat ter and nicotinedelivery in the smoke and the results are set out in Table 1.

TABLE 1 Referring to Table 1 it will be noted that the amount ofnicotine in the smoke in all examples 16 was appreciably higher than inany of the three control samples 7, 8 and 9. The percentage nicotinetransfer (nicotine in smoke compared with nicotine in unsmokedcigarette) was better in examples 1-6 compared with examples 7 and 9.Furthermore the ratio of particulate matter (P.M.) to nicotine ofexample l-6, was superior to that of the control examples 7, 8 and 9 toa marked degree. The increase in value of ratio of particulate matter(P.M.) to nicotine between testings in examples 1 to 6 was notconsidered to be significant.

It has been found and it is indicated by results tabulated in Table 1that, by the addition of small quantities of nicotine pectinate ornicotine alginate an appreciable retention of nicotine can be securedand transferred to the smoke whereby the nicotine content of the smokeis fortified. Furthermore it has been found that the nicotine content ofthe smoke is not appreciably affected by storage and thus the loss innicotine has been found to be no greater than that from the most stableof the control examples used.

passing this through a P.U.C. mill at zero setting and then twicethrough a Manton-Gaulin K3 homogeniser at 3,000p.s.i.

The winnowings slurry and the offal slurry were mixed together, and14.51bs of Sample 4 nicotine pectinate solution were added.

The nicotine fortified slurry was recycled through a P.U.C. mill toachieve thorough mixing and then cast on a Sandvik cast tobacco sheetmachine. The Sandvik machine was run at 13.5 feet per minute with a0.030

in casting gate and a 0.5m. slurry head. This produced 1 1 .251bs. ofsheet.

The nicotine content of the sheet immediately after manufacture was 3.15percent. Some of the sheet was stored for eight weeks in open containersunder atmospheric conditions of 21C and 60% RH. The nicotine contentafter eight weeks was 3.12 percent, indicating an extremely stablesituation.

The remainder of the tobacco sheet so prepared was cut and manufacturedinto filter tipped cigarettes on a Molins Mk 8 cigarette making machine.The cigarettes were 70mm in length and 25.3mm in circumference and had aduel myria/acetate filter. Twenty-five of the cigarettes weremechanically smoked on an lmperial Tobacco smoking machine to a buttlength of 2mm longer than the filter overwrap material using a 35ml, 2second duration puff once per minute. The smoke condensate collected onCambridge glass fibre filter pads was analysed for particulate matterand nicotine by weighing the wet deposit on each filter, analysing thedeposit for nicotine content by steam distillation (Willits method) andanalysing the deposit for water content by gas chromotography. Theparticulate matter Table 1 Series 1 Nicotine P.M.* 1n Smoke Nicotine inSmoke Nicotine Transfer P.M.

in ((Mg/Cig.) (Mg/Cig.) 7t Nicotine Ratio TYPE Material Example 1 2.8630.1 29.0 3.61 3.12 17.1 15.2 8.3 9.3 Example 2 3.90 32.4 30.0 5.02 4.2617.3 14.7 6.4 7.0 Example 3 2.67 28.2 25.5 3.65 3.06 18.4 15.2 7.7 8.3Example 4 3.93 29.7 27.1 4.91 4.42 16.8 15.6 6.1 6.1 Example 5 2.78 28.026.6 3.62 3.03 17.6 14.8 7.7 8.8 Example 6 4.33 25.4 25.6 5.50 4.79 17.014.5 4.6 5.4 Example 7 0.78 17.1 17.2 0.75 0.68 13.0 11.6 27.3 253Example 8 1.44 27.4 1.67 15.6 16.4 Example 9 1.93 31.4 2.16 14.4 14.5

' Denotes particulate matter free from water and nicotine.

SERIES 3: EXAMPLES 10-20.

EXAMPLE 10 (P.M.) level is thus water and nicotine-free. The resultsobtained are set out in Table 2.

EXAMPLE 11 A sheet of reconstituted tobacco was prepared according tothe method on Example 10 but 14.5lbs of Sample 5 nicotine pectinatesolution was used.

The sheet so prepared had a nicotine content of 2.99 percent aftermaking and 2.95 percent after eight weeks storage under condition of 21Cand 60% RH.

Filter tipped cigarettes made to the specification outlined in Example10 gave the results listed in Table 2 when analysed by the standa'rdmethods set out in Ex ample l0.

EXAMPLE 12 A sheet of reconstituted tobacco was prepared in accordancewith the method in Example 10 but l4.5lbs of solution Sample 6 nicotinealginate was substituted for the nicotine pectinate solution.

The sheet had a nicotine content of 3.00 percent after casting and 2.97percent after eight weeks storage under conditions of 21C and 60% RH,indicating a vary stable product.

Filter tipped cigarettes manufactured and analysed according to themethods stated in Example 10 gave the results set out in Table 2.

EXAMPLE 13 The sheet of example 10 was made up as described in thatexample. Instead of l4.5lb of Sample 4 nicotine pectinate solution, l2lbof the sample 4 solution was added to 20lb (oven-dry weight) of sheetmixture whereby the final nicotine content of the cast sheet was 2.08percent rather than 3.15 percent.

Again the sheet was made into cigarettes and smoked in the standard waydescribed in example 10 and analysed according to the method of examplel0. The results are listed in Table 2.

EXAMPLE 14 The sheet of example 10 was made up as described in thatexample, but 12lb of sample nicotine pectinate solution was added to20lb (oven-dry weight) of the basic tobacco mixture to provide anicotine content of 2.12 percent.

The sheet was made into cigarettes, smoked and tested as described inexample 10. The results are set out in Table 2.

EXAMPLE l5 The sheet of example was again prepared but had added theretol2lb of sample 6 nicotine alginate solution to lb (oven-dry weight) ofbasic tobacco mixture to provide a final nicotine content of 2.09percent. The sheet was made into a cigarettes, smoked and analysed asdescribed with reference to example 10.

EXAMPLE 16 Cut rolled stem (processed mid rib) was treated with nicotinepectinate to increase its nicotine content to that of commonly usedtobacco lamina grades.

lb of the stem containing 12 percent moisture and 0.56 percent nicotinewas placed in a polythene bin and 17%lb of sample 7 nicotine pectinatesolution added in small portions. The mixture was stirred with a paddleto minimise the formation of lumps and to ensure an even application ofthe nicotine pectinate solution to the stem.

The mixture was allowed to stand overnight and then dried back to 15percent moisture in a gas fired rotary drier. The material had anicotine content of 1.64 percent.

The material was then manufactured into filter tipped cigarettes on aMolins Mk 8 cigarette making machine. The cigarettes were mm in lengthand 25.3mm in circumference and had a dual myria/acetate filter. Theyweighed 1.040g and had a pressure drop of 1 18mm of water.

The cigarettes were smoked using the standard methods previouslydescribed in Example 10 and gave the results listed in Table 2 using theanalysis technique set out in Example 10.

EXAMPLE 17 The objective was to prepare a substitute smoking material inthe form of a sheet such that it contained approximately 2 percent ofnicotine and was completely free from any form of tobacco.

To prepare the sheet material, a solution of 35g of slow-set citruspectin (obtained from H. P. Bulmers Ltd.) in 700 ml of water wasprepared with the aid of a Silverson mixer. The slow-set citrus pectinhad a degree of esterification of 63 percent and an acidity of 1.6milli-equivalents per gramme. A second mixture was prepared bydispersing 30g calcium carbonate, 5g potassium carbonate, 5g celite(Hyflo Super Cel grade), 5g magnesium hydrogen phosphate and 2g titaniumdioxide in 250ml of water. To this suspension was added 6g of citricacid.

This slurry of inorganic materials was added to the citrus pectinsolution and thoroughly mixed with the Silverson stirrer. A thirdsolution of 9g of Sample 2 nicotine pectinate in 250ml of water was thenadded, followed by 5g of glycerol. The resulting slurry was thoroughlymixed again, and then passed through a Premier 84 colloid mill adjustedto a running clearance of 0.003in to remove any lumps.

The slurry was cast on a continuous stainless steel band using an 1.1mmcasting gate and dried using Infra Red heating lamps. The dried sheetwas moistened to facilitate removal and doctored off the band.

The prepared sheet was cut at 40c.p.i. using a Hauni sample cuttingmachine, Model TSH V and manufactured into filter tipped cigarettesusing an Eflta-Werke Privileg hand machine. These cigarettes were 83mmlong, 25mm in circumference and contained 1.0g of filler material. Thefiller material contained 1.93 percent nicotine. The filter was a monoacetate type.

When smoked and analysed by the standard methods described in Example 10the results listed in Table 2 were obtained EXAMPLE 18 To provide acontrol against which the affects of nicotine fortification can becompared, a sample of commercially available low tar yielding sheetcontaining 0.5 percent of nicotine was cut and manufactured into filtertipped cigarettes in the manner described in Example 10. The cigaretteswere 70mm in length and 25.3mm in circumference and contained 0.70g ofsheet.

When smoked under the standard conditions of Example 10 and analysed asdescribed in Example 10, the Table 2 results were obtained.

EXAMPLE l9 To provide a standard against which the examples l0-l8 couldbe compared, a standard filter tip cigarette. commercially available inthe United Kingdom and being of the same specification as the cigarettesreferred to in Example were smoked and analysed by the standard methodsset out in Example 10. The nicotine content of the filler in thecigarette was determined before smoking as 2.01 percent. The smokeanalysis is given in Table 2.

EXAMPLE 20 To demonstrate the effectiveness of nicotine pectinate as ameans of increasing the nicotine content of 10 stem (processed mid rib),a control sample of untreated stem containing 0.66 percent nicotine wasmanufactured into filter tipped cigarettes in the manner described inExample 16 and with the same physical dimensions as the cigarettes inExample 16. When smoked and analysed using the standard methodsdescribed in Example 10 the results set out in Table 2 were obtained.

The ratio of particulate matter (P.M.) to nicotine is seen to beextremely good in the Examples 1016, being far lower than in the controlExamples 18 and 20 and being of the same order as the commercialcigarette Example 19 for the same initial nicotine content ofapproximately 2 percent (compare Examples 1315 with Example 19).

The results indicate that nicotine derivates of alginic and pectinicacids provide extremely stable nicotine fortification agents which areeffective in efficiently transferring an acceptable percentage of thenicotine to the smoker. Furthermore the fortification agent is useful infortifying not only natural lamina tobacco but also stem (mid rib),reconstituted tobacco sheet and synthetic smoking materials.Particularly with respect to the last two materials, it should be notedthat best results are obtained if the pH of the material is kept belowapproximately 6.5.

Table 2 Series 2 Nicotine content of material Mean no. P.M.* NicotineFilter Nicotine P.M. When After 8 of puffs in smoke in smoke RetentionTransfer Nicotine TYPE made weeks per cig. (mg/cig.) (mg/cig.) RatioExample 10 3.15 312 8.7 17.0 1.53 54.1 16.6 11.1 Example 11 2.99 2 958.1 14.2 1.41 54.6 18.6 10.1 Example 12 3.00 2.97 8.4 17.3 1.56 53.018.6 11.1 Example 13 2.08 2.06 7.0 14.2 0.98 53.7 18.5 14.5 Example 142.12 209 7.7 17.1 1.08 55.9 18.7 15.8 Example 15 2.09 2 06 7.6 15.8 1.1453.0 20.3 13.9 Example 16 1.64 8.2 10.0 0.71 56.1 15.1 14.1 Example 171.93 8.7 12.3 1.70 29.0 17.0 7.2 Example 18 0.50 8.0 9.1 0.30 52.0 19.0330 Example 19 2.01 11,6 21.0 1.49 47.8 21.2 14.1 Example 20 0.66 8.411.4 0.29 54.2 14.6 39.4

* Denotes particulate matter free from water and nicotine.

TABLE 2 Referring to Table 2 it will be noted that the additive isextremely stable. In all cases only a small loss of nicotine derivativeof pectinic or alginic acid was noted in the eight weeks followingapplication to the base tobacco material. This is far superior toprevious attempts to find a stable nicotine fortification material.

Regarding the nicotine transfer figures, it will be seen that these areextremely good for all examples which were fortified. Over 16 percent ofthe nicotine in each starting material was transferred to the smoke andpresented to the filter. It will be seen that this compares favourablywith the standard or control cigarette results. Thus the commerciallyavailable cigarette tested produced a transfer figure of 21.2 percent.The test results indicate that very little reduction in this figure isto be expected even with fortified materials and blends.

It will be appreciated that the materials tested were all basicmaterials in Examples 10-17 i.e. no blends of materials were used.However, such blends could of course be used in any commercial use ofthe material.

mixture or the individual materials.

Furthermore Curie point pyrolysis followed by gas/- liquidchromotography tests on the nicotine pectinate and nicotine alginateemployed'indicated that maximum yield of nicotine occurs between 500 and550C i.e. at the temperature immediately behind the burning coal of acigarette. It would appear from the results obtained that nicotinederivatives pectinic and alginic acids offer substantially attractiveadditives to tobacco products providing a nicotine agent which willfortify the nicotine content of the product whilst remaining relativelystable over a period of months and yielding the nicotine at the optimumtemperature of 500 to 550C and yet being a relatively acceptable andharm less ingredient making it a most suitable and attractive additive.

Pectins, particularly those from tobacco plants, are well known asbinders or sheet strengtheners in the manufacture of reconstitutedtobacco sheet or synthetic smoking materials and thus the addition ofnicotine pectinate has the added attraction that the pectinate so addedassists in binding and strengthening reconstituted or synthetic sheet.Thus not only is the sheet fortified with nicotine but also astrengthening agent is added without the need to add additionalsubstances as is done in reconstituted or synthetic sheet manufacture.

With the present invention there is provided a stable and effectivenicotine fortification material being the nicotine derivatives of apolyuronic acid.

Although all examples have used nicotine derivatives of polygalacturonicand polymannuronic acids only, it

is considered that any polyuronic acid can be used in view of theclosely similar properties of these acids. Thus nicotine derivatives ofpolyglucuronic acid and of polyguluronic acid would be useful nicotinefortification agents but, like all polyuronic acids other thanpolygalacturonic and polymannuronic they are not readily available inbulk and thus at this time are not commercially attractive. However thisdoes not detract from their effectiveness. The examples have beenlimited to the two readily available and commercially attractivepolyuronic acid derivatives but the invention embraces the nicotinederivatives of all polyuronic acids.

What we claim is:

l. A process for making a smoking material selected from the groupconsisting of tobacco, reconstituted tobacco and substitute tobaccowhich comprises adding 5. The process of claim 4 wherein the additive isa nicotine derivative of pectinic acid having a degree of esterificationof 25-40 percent and an acidity of 1.5'to 3.5 milliequivalents per gram.

6. The process of claim 1 wherein the material is a nicotine derivativeof polymannuronic acid.

7. The process of claim 6 wherein the derivative is nicotine alginate.

2. The process of claim 1 wherein the material is a nicotine derivativeof polygalacturonic acid.
 3. The process of claim 2 wherein thederivative is nicotine pectinate.
 4. The process of claim 3 wherein theamount of dertive is 3 percent to 13 percent by weight.
 5. The processof claim 4 wherein the additive is a nicotine derivative of pectinicacid having a degree of esterification of 25-40 percent and an acidityof 1.5 to 3.5 milliequivalents per gram.
 6. The process of claim 1wherein the material is a nicotine derivative of polymannuronic acid. 7.The process of claim 6 wherein the derivative is nicotine alginate.